In the conventional reciprocating engine a connecting rod links the piston to a crank on the crankshaft. The connecting rod turns the crank during the power stroke and the crank then continues to rotate and drives the piston back up the cylinder. In this way, the crankshaft converts the movement of the pistons into rotary power. In order to turn the crank, the connecting rod has to be slanted in the delivery of combustion energy to the crankshaft. At the moment when the greatest cylinder pressures are being exerted, the connecting rods are slanted between the pistons and the crank. This slant of the connecting rod reduces the efficiency of the transmission of energy.
The prevailing design of automobile engines is to shorten the stroke and to repeat the cycle faster to compensate for deficiencies inherent in the slanted rod design. However, shortening the stroke and repeating the cycle faster limits the ability of the engine to fully utilize the flame spread pattern during combustion. Accordingly, the thermal efficiency of the engine is reduced.
There have also been attempts at improving engine performance by other methods such as electronic controls, freer airflow patterns, and fuel injection. However, the increases in performance are moving forward in relatively small strides because of the limitations of the connecting rod/crank design.
What is needed is a reciprocating engine that provides an improved connecting rod/crank and crankcase design for transmitting the movement of pistons into rotary power.